The invention relates generally to a measuring tool and method and, more particularly, to a tool and method for measuring relative concentricity deviations in a confined space between two circumferential elements, such as between a turbine rotor and a turbine diaphragm.
For a turbine to operate more efficiently, during its assembly or during an overhaul, it is advantageous for the rotor to meet certain concentricity requirements relative to the stator. It is often desired to measure the concentricity of the rotor and stator with the rotor left in place. A difficulty with this approach, however, is that the small radial clearances between the rotor and stator diaphragm do not allow for the measurements to be taken manually due to the lack of access and constrained space.